We've seen a number of rumours that the HTC HD2 will be getting an update to Windows Phone 7 Series. However, due to one simple technical requirement it closes off the rumour.
The hardware guidelines are quite specific in that phone manufactures need to have a specific processor (ie, the 1GHz Snapdragon from Qualcomm), a high-res screen, a 5 megapixel camera and a 3.5mm headphone jack... which the HTC HD2 already has. However, one of the "strict" requirements of the chassis 1 phones is that they also need to have three hard buttons below the screen. The HTC HD2 happens to have five which breaks the deal.
That's the official line from Microsoft, at any rate. Natasha Kwan, General Manager for Microsoft's Mobile Communications Business in the Asia-Pacific region, told APC that the HD2 'doesn't qualify because it doesn't have the three buttons.
We speak of the HD2 in this post because it's the phone that most people seem to want running Windows Phone 7 Series. These hardware requirements are not singling out the HD2 though and cover all current Windows Mobile 6.X phones that also meet the rest of the requirements.
As it stands, it is unclear if the only reason is because of having a couple of extra buttons as there are other unknown hardware requirements that the HD2 apparently doesn't meet. Either way, it seems that the HD2 is not getting the update, so for those who already have the phone then it's bad luck for you unfortunately.